Edwin j



(No Model.) l

E'. J. HOUSTON.

ELECTRIC INCANDESGENT LAMP.

Patented June 6, 1882.

N PETERS. Phmoumagraphv, wnmingmn, D. C

UNITED STATES PATENT OEEIcE.

EDWIN J. HOUSTON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE AMERICAN ELECTRIC COMPANY, OF NET BRITAIN, CONN.

ELECTRIC INCANDESCENT LAMP.

SPECIFICATION forming part of Letters Patent No. 259,017, dated June 6, 1882.

Application lcd March 14, 1882. (No model.)

To all whom it may concern Be it known that I, EDWTN J. HoUs'roN, of the city and county of Philadelphia, State of Pennsylvania, have invented certain new and useful Improvements in Electric Incandescent Lamps, ot' which the following is such a description as will enable those skilled in the art to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The object of my invention is to improve the general construction and to increase the durability and efficiency of incandescent lamps. These ends I accomplish by an improved means offorming the electricconductingj oints between the ends of the incandescent carbon iilament and the conductors conveying the current into the lamp, and by other details of construction, all of which will be hereinafter more fully described.

Considerable difficulty has hitherto been eX- perienced in obtaining a good electrical conducting-joint between the ends of the carbon filament and the conducting-wires attached thereto. 1 obtain such ajoint by the following means: To the ends of the carbon tilament, which I prefer to make out of paper-pulp or card-board, prepared and carbonized in the usual manner, I attach short lengths of wire made of iron or other material capable of entering into chemical combination witl; carbon by any suitable means-as, for example, by wrapping the wire about the filament or by passing it through a hole in the ends ot the filament, and bring the iron wires into as intimate contact with the ends of filament as possible. I then by preference insure better contact by electroplating the junction with a thin deposit of iron. This being done I still further increase the electrical conductivity and secure a more intimate union between the junction of the wire and the filament by converting the iron into steel or a carbide containing more carbon than ordinary steel. This latter process may be eii'ected by exposing the junction,whle highly heated by any means--as by the passage of an electrical currentto any hydrocarbon gas or vapor. Under these circumstances, as is well known, the hydrocarbon is decomposed and carbon of high electrical conductivity is deposited on the heated surfaces. If any of these surfaces be formed of any other substance that, like iron, is capable of entering into chemical combination with the carbon, it will so combine. In the case ofiron it will be converted into steel, while pure carbon'will be deposited on thejunction and on the filament, thus insuring a true chemical contact at the junction. If so desired, the deposition of the carbon on the other portions of the tilament may be prevented by any suitable means. Instead of exposing thejunction to hydrocarbon gases or vapors while the parts are incandescent, it may, if so desired, be dipped in any hydrocarbon liquid and carbon deposited thereon by simple electrolytic action.

I sometimes slightly modify the above-described processes as follows, viz Before the paper or pulp forms are carbonized I secure the iron wires to the ends thereof by wrappingthem with strands of flax or other pliant carbonizable material. During the ordinary process of carbonization, which is then resorted to, the pliant iibrous material is not only carbonized, but partially converts the iron into steel. Immediately on removal from the furnace I electroplate the junction with iron, and then eX- pose the filament and its conductingwires, while heated to electrical incandescence, to the same hydrocarbon vapor or gas that is employed for the purpose of improving the electrical conductivity and homogeneity ofthe lilament. The length of iron or other wire thus connected to the carbon is not passed through the globe, as a good joint cannot be formed between the iron and glass, but is attached to a piece ot' platinum or other conductor suitable for forming a tight joint at the point where the leadingin conductor passes through the walls of the globe. By thus constructing the leading-in conductor ot' two parts, one capable of entering into chemical union with carbon and the other suitable for sealing in glass, I insure a tight joint at the point of sealing as well as a good electrical connection between the carbon and the leading-in conductor.

Figures l to l0 show the various details of my invention as applied to my improved construction of incandescentlamps. Fig. 1 is a view of the completed lamp with its incandes- IOO cing lament, showing the support thereforand its inclosing glass globe or envelope. Fig. 2 is a vertical section through part of the lamp, showing the method of supporting the same and the device for turning the current into or away from the lamp. Fig. 8 shows a modified form of sealing for the conducting-wires. Fig. 4 shows in detail a simple form of supportingclamp for the lamp. Fig. 5 shows the method rt support for a bracket-lamp. Figs. 6 and 7 show the construction ofthe conducting-wires. Figs. 8, 9, and 10 show the details of the mechanism for turning the light on or oft'.

In Fig.1 is shown a lamp completed according to the details of myinvention, and ready for placing on its supporting-bracket. C is the carbon filament. j j are the steeliled and carbonized junctions, prepared in the manner previously described. The conducting-wires A and B, leading to the junctions jj, are fused into the ends of two glass tubes, w 1v, by melting the glass around them,as at a a. These tubes are eonstricted, at b Z, near their points of attachment to the supporting mass S S S S", which is also of glass. The glass mass S S S S w w, which forms the support for the carbon filament O, has an inclosing globe, S, also of glass, securely attached to it by fusing it to the neck ofthe supportingstand at S S',

as shown, and exhausted of air in the usual manner. Before closing the lower part of S S, and by preference before attaching the globe S, melted sealing-waxis run in the tubes w w, so as to completely surround the conductingwires. The end is then fused at the constricted portions b b. The object of the tubes 'w w,with their inclosing sealing-wax, is to prevent the entrance of air into the chamber containing the carbon llament. Sealing-waxor any other partially-flexible substance answers this purpose admirably, and I have used it with considerable success for sealing the wires connected with highly-exhausted glass tubes. It probably owes its efficiency to the strength of its adhesion both to the glass and the conducting-wire, and also to the fact that purely local expansions ofthe conducting-wires are not so liable lo fracture it as to fracture a more brittle material. Other sealing materials may, however, be used in place of the wax. The lower part of the glass support is shaped as shown, and fashioned at its bottom into the form of a hollow cylinder, as seen at S S. At some little distance from the lower end of S Sll brass or copper rings Y X are placed, one inside and the other outside the glass cylinder. These rings, which are attached to the glass in any suitable manner, form the terminals of the conducting-wires A and B, and afford a ready means of placing the lamp in electrical connection with the conductors furnishing the electric current. The bracket or chandelier that supports the lamp is provided with two concentric conducting-rings, suitably insulated from each other and connected respectively to the wire leading to and from the source furnishing the electric current. These rings are placed such a distance apart as to permit the rings X and Y, connected to the supporting-stand S S, to be forced between them. They maybe caused to press more firmly against the conductors X and Y, and thus insure better electrical contact, by means ofsuitably-placed springs, or the outer ring of the supporting-bracket may be firmly clamped against the outer ring of the lamp-stand, by means of the contrivance I have shown in connection with Figs. 2 and 4. This contrivance consists in a simple hinged joint which holds the two halves of the outer ring, L. Lips formed on the other ends of the sections are connected by a screw, Q, by means of which the diameter ofthe ring can be varied within certain limits.

I have also shown in Figs. 2, 8,9, and l0 simple means by which the current can be caused to flow through or past the lamp, thus lighting or extinguishing it. This consists of the screw or spindle P, seated in and passing through ring L, and preferably made of some insulating material or resting in an insulating sleeve. By turning the screw a quarterrevolution metallic contact is established between L and M by means of the devices to be presently described, and the lamp is thus extinguished, the ineandescentportion being shortcircuited. When in this position another quarter-turn breaks the short circuit between L and M, and thus lights the lamp.

Fig. 8 is a horizontal transverse section through x of Fig. 2. Fig. 9 is a vertical transverse section through P on line y y of Fig. 2, showing the position ot' parts when the lamp is lighted. Here the metallic piece P', extending through the insulating material of P and suitably attached thereto, is shown as out of contact with the conducting wires or springs m and Z, connected respectively with M and L. Under these conditions, it' the lamp be in its socket, the current is forced to pass through the carbon filament.

Fig. 10 shows the device with the screw P turned so as to bring the pin or conductingpiece F simultaneously into contact with springs or wiresm l and close the circuit around the lamp by forming a short circuit from L to M, thus extinguishing the light.

In Fig. 3 I have shown a modified form of the sealing-joint shown in Fig. l at w w. The letters refer to similar parts to those shown Fig. I. In the lower p art of the stand S S, I provide a tube, ai', which is filled with melted wax in a manner4 similar to that described in connection with Fig. l. I sometimes adopt this method in preference, so as to avoid the possibility of injury to the vacuum in S, due to the leakage ot' gases evolved from the wax in ai fw. In this form, the wax being entirely within the supporting-stand S S, injury from4 leaking is much less liable to occur. To still further avoid the danger from this source I sometimes purposely leave an opening at o in the lower part of the tube w', so as to facilitate the escape of compressed vapors.

I have shown in Fig. 5 the mode of attachlIO ing the lamp to its supporting bracket orstand.

The conducting-wires, which are suitably insulated, are passed through the hollow tube forming part of the bracket. The conductingrin gs L and M are separated from one another and from the metal ot the supporting-bracket by insulating material. One of the conductin gwires is brought into metallic contact with the outer ring and the other to the inner ring. ro In order to place the lamp on the bracket, the screw Q, is turned so as to open the ring L. The lamp is then placed therein, so thatits ringX is broughtinto metallic contact with L, andY into metallic contact with M. The screw Q is then turned so as to rmly clamp the ring L,

and the lamp is ready for use.

In Figs. 6 and 7 I have illustrated some of the different methods of forming the conducting-Wire.

2o A A' is the end of the carbon fila-ment. jj are the joints, steeliied and carbonized, as already explained. A A are the lengths of iron wire. jj' arethe welded or wrappedjoints. The wires A. A are either copper or platinum.

That I claim as my invention is l. rlhe herein-described method of forming a good electrical connection with the carbon strip or iilamentof an incandescent lamp, consisting in fastening the strip or iilament to a conductor ot iron or other conducting substance capable of entering into chemical combination with carbon, and then carbonizing the conductor thus attached.

2. The hereinmlescribed method ot' forming 3 5 an electrical connection between the carbon strip or filament of an incandescent electric lamp and the outside conductor, consisting` in fastening the strip or filament to a conductor of a material capable ot' entering into chemical combination with carbon, electroplating the joint with a similar material, capable also of entering into chemical combination with cai1` bon, and then converting thejoint thus formed into a carbide of the material employed.

3. The herein-described method ot' forming an electrical connection with the strip or lilament of an incandescent carbon lamp, consisting in fastening said strip to a length of iron conducting-wire, and then converting theiron 5o thus attached into a carbide.

4. The herein-described method ot' forming an electrical connection with the strip or filament of an incandescent carbon lamp, consisting in fastening saidstripto an iron conductor, electroplating the joint with iron or other suitable metal, and then treating the joint thus formed so as to convert the iron into a carbide.

5. The herein-described method of forming 6o an electrical connection between the strip or lament of an incandescent carbon lamp, consisting in connecting the strip or filament before carbonization to an iron conductor, wrapping theiron with a carbonizable material, carbonizing the strip or filament with the conductor thus attached, and afterward electroplating` with iron and heating to incandes cencc in a carbon vapor, gas, or liquid.

G. A compound leading-in conductor for an incandescent light, composed of platinum at 7o the point where it passes through the walls of tho glass inclosing globe and of iron or similar material capable of entering into chemical combination with carbon at the point where it is attached to the carbon strip or filament.

7. In an incandescent electric lamp, a carbon strip or filament, in combination with a leading-in conductor ot' carbide of iron covered with carbon at the point ot'junction, deposited in the manner set forth.

S. In an incandescentlarnp, acompoundconductor for the purpose of carrying the current to and from the carbon filament, consisting essentially of a metallic wire of suitable material for sealing into the glass support by melting the glass aroundit, welded to or wrapped around one end of a wire capable ot' entering into chemical combination with the carbon ot' the Jfilament, and combined chemically in the manner substantially as described with the end ofthe filament and with other carbon deposited thereon.

9. Aglass supportingand an inclosing globe for the incandescing tilament of an electric lamp, fashioned at its bottom into the form of a hollow cylinder, S S", to the inside and out side of which respectively are attached the conducting-rings X Y, connected to the ends of the lament.

l0. The combination, substantially as derocscribed, of an electric lamp provided at its base with a conducting-ring forming a terminal of its incandescing portion, and a ring-socket for holding the lamp formed in two parts, said ring being provided with a suitable clamping device, and connected with the conductor by which the electric current is supplied to the lamp.

11. The combination ot' the double ring socket L and M and sbunting-key P.

12. The combination ot' the double ring socket L M, springs or conductors projecting from said rings, and the turning screw or spindle P, mounted in the outer ring and provided with means for completing and breaking the circuitbetween the springs.

. EDWIN J. HOUSTON.

Witnesses:

. EDWARD W.VoGDEs,

Gmo. W. SoHooK. 

